mc9s12hz256v2 Freescale Semiconductor, Inc, mc9s12hz256v2 Datasheet - Page 37

• Manufacturer Part Number: mc9s12hz256v2
• Description: Hcs12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

1.5
1.5.1
EXTAL and XTAL are the crystal driver and external clock pins. On reset all the device clocks are derived
from the EXTAL input frequency. XTAL is the crystal output.
1.5.2
An active low bidirectional control signal, it acts as an input to initialize the MCU to a known start-up
state, and an output when an internal MCU function causes a reset.
Freescale Semiconductor
Mnemonic
V
V
V
V
DDM1,2,3
V
V
SSM1,2,3
V
V
V
V
V
V
V
V
V
V
V
DDPLL
SSPLL
V
DDX1
DDX2
SSX1
SSX2
DDR
LCD
DD1
SSR
DDA
SSA
SS1
SS2
RH
RL
Detailed Signal Descriptions
EXTAL, XTAL — Oscillator Pins
RESET — External Reset Pin
Nominal
All V
signal transitions place high, short-duration current demands on the power
supply, use bypass capacitors with high-frequency characteristics and place
them as close to the MCU as possible. Bypass requirements depend on
MCU pin load.
Voltage
5.0 V
2.5 V
5.0 V
5.0 V
5.0 V
5.0 V
2.5 V
5.0 V
0 V
0 V
0 V
0 V
0 V
0 V
0V
SS
pins must be connected together in the application. Because fast
Voltage reference pin for the LCD driver.
Internal power and ground generated by internal regulator. These also allow an external source
to supply the core V
External power and ground, supply to pin drivers and internal voltage regulator.
External power and ground, supply to pin drivers.
Operating voltage and ground for the analog-to-digital converter and the reference for the internal
voltage regulator, allows the supply voltage to the A/D to be bypassed independently.
Reference voltage high for the ATD converter.
Reference voltage low for the ATD converter.
Provides operating voltage and ground for the phased-locked Loop. This allows the supply
voltage to the PLL to be bypassed independently. Internal power and ground generated by
internal regulator.
Provides operating voltage and ground for motor 0, 1, 2 and 3.
MC9S12HZ256 Data Sheet, Rev. 2.05
Table 1-9. Power and Ground
DD
/V
SS
voltages and bypass the internal voltage regulator.
NOTE
Description
Chapter 1 MC9S12HZ256 Device Overview
37